Answer:
The volume flow rate of air is 
Explanation:
A random duct is shown in the below attached figure
The volume flow rate is defined as the volume of fluid that passes a section in unit amount of time
Now by definition of velocity we can see that 'v' m/s means that in 1 second the flow occupies a length of 'v' meters
From the attached figure we can see that
The volume of the prism that the flow occupies in 1 second equals

Hence the volume flow rate is 
Answer:
Fatigue occurs under conditions of high elastic stress, high stress fluctuations and high rate of loading
Explanation:
According to many definition of fatigue failure the fatigue occurs when in an especifyc point of the object there is involved many forces and tensions.
That tensions needs to be big in magnitud, de variations of the efforts it has to be with a lot of amplitude and the loading in the object it has to be with a lot of number of cycles.
If in the all of these three conditions are present the fatigue failure it would appear.
Answer:
a) Ql=33120000 kJ
b) COP = 5.6
c) COPreversible= 29.3
Explanation:
a) of the attached figure we have:
HP is heat pump, W is the work supplied, Th is the higher temperature, Tl is the low temperature, Ql is heat supplied and Qh is the heat rejected. The worj is:
W=Qh-Ql
Ql=Qh-W
where W=2000 kWh
Qh=120000 kJ/h

b) The coefficient of performance is:

c) The coefficient of performance of a reversible heat pump is:

Th=20+273=293 K
Tl=10+273=283K
Replacing:

Answer:
Object-Oriented Software Engineering Using UML, Patterns, and Java, 3e, shows readers how to use both the principles of software engineering and the practices of various object-oriented tools, processes, and products.